Traveling-grate furnace



(No Model.) I/ 3 SheetsSheet 1.

v F. H. RICHARDS.

TRAVELING GRATE FURNAGE.

Patented Mar, 27, 1894.

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Mi'nesses:

(No Model.) a Sheets-Shet 2.

P. H. RICHARDS. TRAVELING GRATB FURNACE.

No. 517,067. Patented Mar. 27, 1894.

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s Sheets-Sheet 3.

{No Model.)

. P. H. RICHARDS. TRAVELING GRATE FURNACE.

No. 517,067. Patented Mar. 27, 1894,.

Witnesses;-

THE NATIONAL uflmanAPnma colIlPANY.

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terns PAENT Carton.

FRANCIS H. RICHARDS, OF HARTFORD, CONNECTICUT, ASSIGNOR TO ECKLEY B. COXE, OF DRIFTON, PENNSYIJVANIA,

TRAVELlNG-GRATE FURNACE.

sPEGIFICATION forming part of Letters Patent No. 517,067, dated March 27, 1894.

A Application filed December 26, 1893. Serial No.49 L649. (No model.)

To aZZ whom it may concern.-

Be it known that I, FRANCIS H. RICHARDS, a citizen of the United States, residing at Hartford, in the county of Hartford and State 5 of Connecticut, have invented certain new and useful Improvements in Traveling-Grate Furnaces, of which the following is a specification.

This invention relates to that class of trav- I cling-grate furnaces which is described in Letters Patent of the United States No. 499,716, granted to Eckley B. Coxe, June 20, 1893; it is also, in part, in the nature of animprovement upon the traveling grate or fur- I nace-floor described in United States Letters Patent No. 510,573, granted to E. B. Coxe and F. H. Richards, December 12, 1893.

The object of the invention is primarily to provide an improved furnace of the class specified in which the fuel after it is fed to the grate will be carried thereby, first, down an incline during the ignition-period, and then carried along by the traveling grate more nearly horizontally during the latter stages 2 5 of the combustion-period also to so construct and organize the parts of the traveling grate that air may be properly supplied to the fuel thereon through spaces between adjacent and successive grate-bars or furnace-floor plates, and in which said spaces may be automatically increased and decreased in area during the traveling movement of the grate, to vary the supply of air to the fuel during the successive stages of the combustion-period. 5 In the drawings accompanying and forming a part of this specification, Figure 1 is a vertical longitudinal section of a traveling-grate furnace embodying my present invention. Fig. 2 is a vertical cross-sectional view taken in dotted line a-a, Fig. 1, and lookingtoward the right-hand end in said figure. Fig. 3 is a plan view of one of the furnace-floor sections or grate-bars. tion of said floor-section or bar. Fig. 5 is an end view of said floor-section or bar, showing the manner of connection with the endless chain, or grate-bar carrier. Fig. 6 is a diagrammatic View illustrating the method of varying the positions of the floor-sections or grate-bars relative to one another fori'ncreas Fig. 4 is aside eleva-' ing and decreasing the air-spaces between the adjacent sections or bars.

As a framework for carrying the operative parts of the furnace-mechanism, andalsofor protecting said mechanism and. preventing the eftlux of the air-blast, I providemy improved furnace with the usual inclosing-walls at the sides and ends thereof; the lower portions of which walls may consist, as indicated in the drawings, of relatively thin plates connected together at their edges after the usual manner of erecting wrought-iron structuralwork. The sidewalls are designatedin a general wayby2 and 4, respectively, and the .furnace-chamberC is shown as covered, near its front end, by a reverberatory arch, A, at the rear end of which the boiler (if one is used) will be located; a portion onlyrof the rear end of the furnace is shown. 7 The forward end of the furnace is provided with the usual end-wall, 3, the upper front end of the furnace, intermediate to the arch A and endwall 3, being covered by a suitable top-wall, 8.

As shown in the drawings, the hopper for delivering the fuel to the traveling grate, and designated by H, is preferably located intermediate to the forward end of the arch A and rear end of the plate 3, it terminating at its lower end preferably in alignment with the inner face of said arch. It is obvious that the general construction of the framework just described may be modified, as circumstances may require, without departing from the spirit of my invention.

Similarly as in the Patent No. 499,716 hereiubefore referred to, the floor of the furnacechamber C consists of an endless traveling grate, designated in a general way by G, the preferred construction and organization of which will behereinafter more fullydescribed, go it consisting essentially of a series of transversely-disposed parallel floor-beams or gratebars, designated in a general way by N, which are secured to, and are carried by, endless chains 50 at either end thereof, which chains run over and are actuated by chain-wheels 12 and let carried upon the shafts 13 and 15, respectively, in a manner somewhat similar to that described in said Letters Patent. Said shafts and chains are or may be actuated by too means of a worm-wheel, 40, fixed to one of said shafts and meshing with a worm, 41, on the driving-shaft 42, which shaft is supported in suitable bearings (not shown) secured to the framework, and is provided with a driving-pulley, 44, at one end thereof, whereby said shaft may be revolved.

The air-supply apparatus for the grate is shown in Fig. 1 as consisting of a series of chambers,a, b, c, (1, located at successivepoints of the'furnace-chamber immediately under the fuel-carrying run of the furnace-floor. Said chambers are supplied with air by means of their respective pipes, a), b, c and d, which are usually provided with regulating valves or gates, at", b, c", 01", respectively, for the purpose of independently regulating the airpressures in the respective chambers, and thereby effecting the combustion of the fuel accordingto the process described and claimed in United States Letters Patent No. 499,715, granted to Eckley B. Coxe, June 20, 1893.

With my improved furnace-floor, as will be hereinafter fully described, the separate chambers a, b, c, d, and the separate supplypipes a, b, c, d, and the valves therefor, may be dispensed with, and a single air-receiving chamber extending below the upper run of the traveling furnace-floor, and one communicating air-supply pipe therefor, be used instead, as shown in dotted lines in Fig. 6. In this case, the supply of air to the fuel supported upon the floor-plates is governed, and the volume so supplied is increased and decreased as required at successive points in the length of the furnace-chamber, by automatically changing the relative position of the several grate-bars to open and close the air-spaces b'et-weeu adjacent successive floorplates during their travel through their circuit.

For supplying fuel to the furnace-floor, I have shown the usual hopper, H, from which the fuel slides downward in a stream, 22, directly onto the grate orfurnace-fioor, substantially after the manner illustrated in said prior Letters Patent. The f urnace-chamber C immediately rearward of the hopper 1-1 is shown as covered by a reverberatory arch, which is shown curved upwardly; and beyond said arch may be placed the boiler or other thing to be heated.

For the purpose of simplifying the illustration of my invention, only such partial views of the described furnace are herein shown as are deemed necessary for a proper understanding of my present improvement, and for this purpose complete elevations are deemed unnecessary.

According to my present improvement, the rate mechanism is set inclined, as best shown b I in Fig. 1, the series of floor-beams or bars bein carried by the endless chains 50 as before stated. Each side of the traveling furnace-floor or grate is shown provided with a series of rollers, 51, whose peripheries project (see Fig. 1) beyond the inner edge of the carrying-chains 50. These rollers, during the rotation of the grate in its travelingcircuit, bear upon, and travel over, tracks or ways, 18 and 19, below the upper and lower runs, 10 and 11, respectively of the grate. These tracks are shown as curved, the upper tracks, 18, being preferably formed upon the upper edges of the side-walls of the air-chamber, designated in a general way by J, and the lower tracks being secured to the inner sides of the walls of the furnace-structure; said mechanism being, in practice, inclosed for the purpose of retaining within the gratemechanism chamber 0 any-leakage of air escaping by way of the edges of the furnacefloor.

As shown in the drawings, the forward chain-wheel 12 is located near the upper forward end of the grate-mechanism chamber 0, and approximately in horizontal alignment with the combustion-chamber C, while the chain-wheel 1 1 is located below said combustion-chamber at the rear end of the gratemechanism chamber C. The chains 50 are of sufficient length to extend over said wheels and be free for slight vertical movement at the portion thereof intermediate to said chain-wheels, as most clearly shown in the diagrammatic view in Fig. 6. This endless chain, in the preferred form thereof herein shown, comprises a series of relatively short duplicate links, which links may be of any suitable construction, they being pivotally secured together at their ends, as shown in Figs. 1 and 6. On its lower side, as shown in Figs. 1 and 6, each link is shown provided with a suitable lug or projection, 6, for engaging the chain-wheels of the grate-mechanism, which wheels have a number of recesses for receiving the projections of the several links. The floor-beams or plates N are each secured as shown in Figs. 1 and 6, to its supporting links near the ends of said links, preferably by means of screw-bolts extending through projections at the ends of the beams and entering the chain-links. The floor-sections or grate-bars are of duplicate construction; and in the preferred form thereof, each section consists of a suitable beam, N, having its upper end flanged transversely at one side thereof to form a fuelsupporting plate, M, the said bar being preferably provided with lugs or projections at the opposite ends thereof, at one side, to provide means for attaching the same to the les s grate or furnace-floor is intended to be toward the left-hand in Fig. 1, as indicated by the arrow shown on the chain-wheel 14:. The floor-sections, when passing over said wheel at the left-hand side thereof, are'sepa' rated as there shown, so that the ashes and cinder from one floor-section will, as this section becomes more inclined, be thrown forwardly and upon the next floor-section, and finally disposed of. By means of the organization shown and described, the floor-sections fully discharge their load of cinder and ashes, and do not become clogged by accumulation thereof between successive floorsections or bars.

One point of advantage in the construction of floor-sections as herein shown and described, is that the several fioor-sections may be duplicates and interchangeable; also that each floor-section, which, as herein shown, includes the fuel-supporting plates and floorbeams, may be readily removed and replaced without interfering with the adjacent floorsections, and that the floor-sections are of a form adapting them to be constructed in a single piece ready for use. In practice, the floor-sections may be made of relatively great length, the depth and thickness of each beam N of the floor-sections being, of course, most suitable for the length of the same.

In the drawings, the floor-beams or gratebars are shown as slotted transversely at their upper edges, there being a number of said slot-s arranged, preferably, about equi distantlyin the length of the grate-bar. These slots or slits are provided simply to accommodate for expansion and construction of the bar, and, in practice, will be very narrow, so as to preclude passage of fuel through the same.

As a means for automatically so changing the positions of the grate-bars relatively to each other as to increase or decrease the airspaces between adjacent bars during' their travel at successive points in the length of the combustion-chamber, each grate-bar is, at each end thereof, secured to and carried by one link of the series of links in the endless chains respectively, and each link is shown provided with a stud and roller at each end thereof, each grate-bar being intermediate to two adjacent rollers, and its position, relative to the next adjacent grate-bar of the series of grate-bars, being governed by the rise and fall of the rollers adjacent thereto in their travel over an undulating or variably-curved track, In Fig. 1 of the drawings, the rollers of the upper run of the endless chains are shown as supported upon and traveling over a track, 18, that is concaved with relation to the combustion-chamber and its reverberatory arch, which track is upwardly inclined toward its forward end. The track in this instance is shown as a curve of uniform radius from end to end, and all of the forward end, as in Fig. 1, but is of slightly irregular contour, it being so shaped at its forward or fuel-receiving end, adjacent to the ignition-point, that the grate-bars in their travel will, as they come opposite this point, have their fuel-supporting edges thrown toward and in close proximity to one another, to substantially close the air-spaces 8 between adjacent grate-bars, this being accomplished, as will be understood by reference to'said Fig. 6, through the peculiar contour ofth'e track and the conforming travel of the rollers and grate-har supportinglinks. The central and end-portions of said track'ar'e-curved so as to gradually open or separate the fuelsupporting edges or portions of the gratebars after these pass the ignition-point, to insure the delivery of a greater'voluine of air to the fuel at the center of the run, and to gradually close said air-spaces, to reduce the air-supply, as the grate-bars approach the delivering-end 'of said run. By this construction and organization, I secure the proper air-blast at the requisite points automatically, thus accomplishing substantially the same result as that secured by the use of aseries of separate air-compartments, deliverypipes and regulating-valves, and requiring the employment of. but one air-chamber and one air-supply pipe. It will be understood, however, that this construction and organization of elements for relatively changing the positions of the grate-bars, to increase or decrease the air-spaces between the same at desired points in the travel thereof as described,

is equally applicable to furnaces of this class employing a series of air-chambers, air-pipes and regulating-valves.

The traveling furnace-floor, when in an assembled condition, lies, with its fuel-supporting portion,'or upper run, in an inclined curve (approximately the arc of a circle) which is'so located as to intersect a line (as, for instance, the dotted line0c-;r) drawn horizontally and longitudinally through the lower portion of the furnace-cl1amber,as will be understood by reference to Fig. 6 of the drawings.

Having thus described myv invention, I claim- 1. In a traveling-grate mechanism for furnaces, in combination, the traveling'furnacefloor comprising aseries of successive overlapping grate-bars having air-spaces between the overlapping'portions thereof, means for imparting a traveling movement, collectively,

to said grate-bars, and grate-bar supporting means, substantially as described, for moving the bars laterally toward and from each other during their traveling movemen't'to open and close the air-spaces between said bars and thereby regulate the air-blast, substantially as described.

2. In a traveling grate mechanism, in combination, curved tracks having undulating track surfaces, a flexible endless furnace-floor having a series of transverse floor-beams and overlapping fuel-supporting bars, or plates, with air-spaces intermediate thereto, means for moving said floor along said tracks and grate-bar supporting means substantially as described for simultaneously moving some of said bars toward, and others of said bars from, adjacent bars to close or open the air-spaces intermediate thereto, substantially as described and for the purpose set forth.

8. In a furnace of the class specified, a traveling furnace-floor comprising a series of successive overlapping grate-bars with successive air-spaces of variable areas intermediate to the overlapping portions of said bars, and grate-bar supporting mechanism adapted for varying the respective air-spaces to bring them to predetermined areas at given points in the travel of said furnace-floor, substantially as described.

4. In a furnace of the class specified, the combination with the furnace-chamber, of a traveling furnace-floor comprising a series of successive grate-bars with air-spaces intermediatethereto, and grate-bar supporting means, substantially as described,forbringing the airspaces to predetermined areas at given points in the length of the furnace-chamber during the traveling movement of said floor, substantially as described and for the purpose set forth.

5. In a furnace of the class specified, the combination with the fnrnace-chamber, of a flexible traveling furnace-floor, located underneath said chamber and comprising a series of transverse grate-bars with air-spaces intermediate thereto, means, substantially as described, for imparting a traveling movement to said furnace-floor longitudinally of the furnace-chamber, and furnace-floor sup porting means, substantially as described, for imparting varying undulating movements to successive portions of said floor adjacent to the furnace-chamber, to change the areas of the air-spaces between bars at successive points in the length of the furnace-chamber, substantially as described and for the purpose set forth.

6. In afurnace of the class specified, in combination, a furnacechamber, a traveling furnace-floor or grate set inclined with relation to said chamber and comprising endless chains, beams supported on said chains transversely thereof and each having a floor-plate or flange at its upper edge at one side thereof and floor-carrying rollers intermediate to the lower ends of said beams; a track for supportingand guiding said rollers, and means for actuating said chains, substantially as described and for the purpose set forth.

7. In a furnace of the class specified, a fur nace-chamber having an upwardly-curved reverberatory arch or deflecting-wall, in combination with an endless traveling furnace-floor or grate located below and at one side of said chamber and having its upper run supported upon an inclined track curved in opposition to the reverberatory arch at one or more points thereof, and means, substantially as described, for actuating said furnace-floor, substantially as and for the purpose set forth.

8. In afurnace of the class specified, a furnace-chamber having an upwardly-curved reverberatory wall, a curved or undulating furnace-floor supporting track inclined substantially as described, and a furnace-floor consisting of endless carrying-chains composed of a series of links pivoted together at their ends, a series of floor beams, each of which is secured to independent links of said chains transversely thereof and has an inclined fuelsupporting plate at its upper edge adapted for partially overlapping the fuel-supporting plate of the next adjacent beam, and rollers secured to the sidesof the chains intermediate to the ends of adjacent beams, substantially as described and for the purpose set forth.

9. In a furnace of the class specified, the combination with the furnace-chamber, of curved inclined furnace floor supporting tracks, located below and at one end of said chamber, endless chains having a series of rollers mounted at one side thereof and adapted to bear upon said tracks during the travel of said chains, a series of floor-beams secured to said chains and having fuel-supporting flanges at their upper ends so disposed relatively to each other as to normally leave air-spaces intermediate to the ends of adjacent flanges, an air-supply chamber perforated at its upper end and located below the upper end of the furnace-floor, and means to actuate said furnace-floor, substantially as described and for the purpose set forth.

10. In a furnace of the class specified, the combination with the furnace-chamber, of a. series of floor-beams secured to and carried by separate links of an endless chain and having inclined fuel-supporting flanges at their upper ends that normally overlap each other a short distance, an air-supply chamber in communication with said furnace-floor, means for imparting movement to said floor, and means, substantially as described, for changing the positions of the fuel-supporting plates relatively to one another during the travel of the same to increase and decrease the airspaces intermediate thereto at successive points along the upper run of said furnacefloor, substantially as and for the purpose set forth.

11. In a travelinggrate furnace, the combination with the furnace-chamber, of tracks located below said furnace-chamber, gratebar-carrying apparatus supported on said tracks means for moving said carrying-apparatus along said tracks, a series of overlapping grate-bars or -plates supported on said carrying-apparatus transversely of the track and having the overlapping portions of the bars located at one side of their connection IIC . with the supporting-apparatus, whereby a movement of one bar toward or from the adacent bar operates to regulate the air-blast by opening or closing the air-spaces between successive bars, and means for moving adja cent bars toward and from each other during the traveling movement of the carrying-apparatus, substantially as described.

12. In a traveling-grate furnace, the com' bination with the furnace-chamber, of'furnace-floor-supporting and guiding tracks inclined and downwardly curved with relation to the furnace-chamber, successive overlapplnggrate-bars having air-spaces between the overlapping portions of said bars, grate-barcarrymg apparatus supported upon said tracks and capable of longitudinal and undulatlng movements with relation to the furnace-chamber, whereby the bars may be moved toward and from each other to regulate the air-blast by opening and closing the air-spaces intermediate to adjacent bars, substantially as described.

13. In a traveling-grate mechanism for f u rnaces, endless chains consisting of a series of substan tially duplicate links pivoted together and having supporting rollers at each end thereof, a series of grate-bars secured one to each link of the chains intermediate to the rollers thereof and having overlapping fuelcarrying plates at their upper ends with the overlapping portions thereof at one side of their connection with said chains, and means for actuating said chains, substantially as described. Y

14.. In a traveling-grate mechanism for furnaces, endless chains consisting of a series of substantially duplicate links pivoted together and having supporting rollers at each end thereof, successive grate-bars secured one to each link of the chains intermediate to the rollers thereof and having overlapping fuelsupporting portions at their upper ends, curved tracks located below the upper and lower runs of the chains, and supporting and guiding said chains through the medium of the rollers thereon, means for moving said chains longitudinally of the tracks, means for changing the relative positions of the overlapping portions of successive grate-bars to increase and decrease the air-spaces intermediate thereto at successive points in the travel thereof to regulate the air-blast, and means for supplying air to the fuel,substantially as described.

15. In a traveling-grate furnace, the combination with the furnace-chamber, of an endless fuel-supporting floor consisting of a series of grate-bars having air-spaces intermediate thereto and so constructed. and disposed that their fuel-carrying faces, collectively, lie in an inclined curve intersecting a horizontal line drawn through the lower portion of the furnace-chamber and at an inclination thereto, and means for moving said furnace-floor longitudinally and vertically of the furnacechamber, substantially as described and for the purpose set forth.

16. In a traveling-grate furnace, the combination with the furnace-chamber, of an endless fuel-supporting fioor consisting of a series of grate-bars having air-spaces intermediate thereto and so constructed and disposed that their fuel-carrying faces, collectively, lie in .an inclined curve intersecting a horizontal line drawn through the lower portion of thefurnace-chamber, driving-wheels supporting and carrying said endless furnace-floor, one of which wheels is located in advance of and approximately in alignment with the furnacechamber, and the other of which is located below and near the rear end of said furnacechamber, means for rotating said wheels to impart a longitudinal movement to said furnace-floor, means for supplying fuel to the furnace-floor at a point near the extreme forward upper end of said chamber, and means for supplying air to said fuel beneath the upper run of said floor, substantially as described and for the purpose set forth.

17. In a traveling-grate furnace, the combination with the furnace-chamber, of an endless fuel-supporting floor consisting of successive grate-bars having overlapping fuelsupporting floors or plates at their upper ends with air-spaces intermediate to the overlapping portions of said flanges, and so constructed and disposed that the fuel-carrying faces of said flanges lie, collectively, in an inclined curve intersecting a horizontal line drawn through the lower portion of the furnacechamber, supporting apparatus therefor, means for supporting, guiding and driving said supporting-apparatus, means for delivering air to the fuel between said grate-bars, means for changing the relative positions of adjacent bars for increasing and decreasing the air-space intermediate thereto at successive points in the travel thereof, whereby to regulate the air-blast, and means for delivering fuel to the upper run of the furnace-floor at the upper forward end of the furnace-chamber, substantially as described and for the purpose set forth.

- 18. In a furnace of the class specified, the combination with the furnace-chamber, of a traveling furnace-floor comprising a series of transverse beams having overlapping longitudinal flanges at their upper sides, and flexibly connected together at their lower sides so as to be capable of a lateral movement independently of each other, tracks located underneath and supporting said beams and having vertically undulating track-surfaces adapted for changing the relative positions of said beams toincrease or decrease the air-spaces between said flanges at given points in the length of the furnace-chamber, and means for moving said furnace-floor longitudinally of said furnace-chamber, substantially as described and for the purpose set forth.

19. In a furnace, the combination with the flections at successive points in the length thereof and adapted for imparting a movement to said grate-bars laterally with relation to each other for increasing and decreasing the air-spaces between said bars and bringing said air-spaces to predetermined areas at given points in the length of the furnacechamber, substantially as described.

FRANCIS H. RICHARDS.

Witnesses:

FRED. J. DOLE, N. E. C. WHITNEY. 

